Rebuilt engine initial fiasco

Just got the 360 block back and reinstalled it. So today was the initial attempted start that turned into a disaster. I changed the exhaust manifolds to 340 HP and as a by product of that the oil filter didn’t fit, so I bought a 90 adapter. The adapter and filter leaked so bad I had to shut down after 3 or 4 minutes. I think what happened was the machine shop told me they primed up the oil pump. Between that and the 20-50 break in oil I was given to use caused to much back pressure. That quick I had a 2’ diameter oil spill.

Now I’m not sure what to do, plus the fact it didn’t run the full 20 minutes at high idle. It was a bad morning to say the least. A side question when I removed the straight set up before installing the adapter shouldn’t there have been any gaskets between the nipple and the plate or block? Just the nipple and plate came off. Need a smaller filter!